1988 yamaha warrior intermittent spark

[Bebe]

Hey guys I'm new here. I have a 88 warrior that has intermittent spark. When I got the bike the guy said it needed a stator.  So I tested the stator and the Source coil has .310,  Trigger coil has .363 an .367,  Alternator side has .05 to .06 on the three. Which all seem in range. I did find that the ignition coil was bad and replaced it. After I  put the new coil on i got spark but only now and then. The bike won't spark while I'm holding the start button,  but as soon as I let off it will spark sometimes. I ended up unplugging the voltage regulator and it will spark every time I let off the start button, but still will not spark while I'm  holding it. What could this be?

 

[MarkinAR]

Most likely CDI.  Normally when you get spark when releasing the start button that's not actual spark but instead is residual voltage bleeding off from the starter circuit.  You can always try baking the CDI for 5 minutes or so at 250 and see if it'll start then.  CDI's usually go bad when the ceramic in the capacitor gets cracked and it gets a bit of moisture.  If it'll start after that, you know it's the CDI and time to get a new one.  Don't buy the cheap $30 chinesium one though, those are only about 2 out of 10 good new in box.

[Bebe]

That makes sense with the residual voltage. I tried baking the cdi today and nothing changed. Do you have any suggestions on which is a good company to get a new CDI box from?

[MarkinAR]

Rick's CDI is the best for Honda by a mile, maybe google and see if there is one for yours? Otherwise good 2nd hand OEM from ebay or new if still available on Partzilla, Babbitts etc. The chinese cheap ones are just terrible. I've had good luck with good 2nd hand OEM parts on ebay.